The Giardia duodenalis 14-3-3 protein is post-translationally modified by phosphorylation and polyglycylation of the C-terminal tail.

The flagellated protozoan Giardia duodenalis (syn. lamblia or intestinalis) has been chosen as a model parasite to further investigate the multifunctional 14-3-3s, a family of highly conserved eukaryotic proteins involved in many cellular processes, such as cell cycle, differentiation, apoptosis, and signal transduction pathways. We confirmed the presence of a single 14-3-3 homolog gene (g14-3-3) by an in silico screening of the complete genome of Giardia, and we demonstrated its constitutive transcription throughout the life stages of the parasite. We cloned and expressed the g14-3-3 in bacteria, and by protein-protein interaction assays we demonstrated that it is a functional 14-3-3. Using an anti-peptide antibody raised against a unique 18-amino acid sequence at the N terminus, we observed variations both in the intracellular localization and in the molecular size of the native g14-3-3 during the conversion of Giardia from trophozoites to the cyst stage. An affinity chromatography, based on the 14-3-3 binding to the polypeptide difopein, was set to purify the native g14-3-3. By matrix-assisted laser desorption ionization mass spectroscopy analysis, we showed that polyglycylation, an unusual post-translational modification described only for tubulin, occurred at the extreme C terminus of the native g14-3-3 on Glu246, Glu247, or both and that the Thr214, located in the loop between helices 8 and 9, is phosphorylated. We propose that the addition of the polyglycine chain can promote the binding of g14-3-3 to alternative ligands and that the differential rate of polyglycylation/deglycylation during the encystation process can act as a novel mechanism to regulate the intracellular localization of g14-3-3

An Update of Carbazole Treatment Strategies for COVID-19 Infection

The Coronavirus disease 2019 (COVID-19) outbreak was declared by the World Health Organization (WHO) in March 2020 to be a pandemic and many drugs used at the beginning proved useless in fighting the infection. Lately, there has been approval of some new generation drugs for the clinical treatment of severe or critical COVID-19 infections. Nevertheless, more drugs are required to reduce the pandemic’s impact. Several treatment approaches for COVID-19 were employed since the beginning of the pandemic, such as immunomodulatory, antiviral, anti-inflammatory, antimicrobial agents, and again corticosteroids, angiotensin II receptor blockers, and bradykinin B2 receptor antagonists, but many of them were proven ineffective in targeting the virus. So, the identification of drugs to be used effectively for treatment of COVID-19 is strongly needed. It is aimed in this review to collect the information so far known about the COVID-19 studies and treatments. Moreover, the observations reported in this review about carbazoles as a treatment can signify a potentially useful clinical application; various drugs that can be introduced into the therapeutic equipment to fight COVID-19 or their molecules can be used as the basis for designing new antivirals

Metabolic Syndrome and Inflammatory Cytokines in Psoriasis.

Obesity negatively affects the pathological states of chronic inflammation, such as Psoriasis and Psoriatic Arthritis. The inflammatory cytokines released by the adipose tissue determine, in addition to inflammation, a condition of insulin resistance, which is also a comorbidity of psoriasis. The state of chronic inflammation unites both psoriasis and obesity. The first is an autoimmune skin disease, where very thick skin layers are evident due to an abnormal proliferation of keratinocytes; obesity, on the other hand, represents one of the possible comorbidities of psoriasis the simultaneous presence in the same subject of two or more diseases

Critical requirement for cell cycle inhibitors in sustaining nonproliferative states

In adult vertebrates, most cells are not in the cell cycle at any one time. Physiological nonproliferation states encompass reversible quiescence and permanent postmitotic conditions such as terminal differentiation and replicative senescence. Although these states appear to be attained and maintained quite differently, they might share a core proliferation-restricting mechanism. Unexpectedly, we found that all sorts of nonproliferating cells can be mitotically reactivated by the sole suppression of histotype-specific cyclin-dependent kinase (cdk) inhibitors (CKIs) in the absence of exogenous mitogens. RNA interference–mediated suppression of appropriate CKIs efficiently triggered DNA synthesis and mitosis in established and primary terminally differentiated skeletal muscle cells (myotubes), quiescent human fibroblasts, and senescent human embryo kidney cells. In serum-starved fibroblasts and myotubes alike, cell cycle reactivation was critically mediated by the derepression of cyclin D–cdk4/6 complexes. Thus, both temporary and permanent growth arrest must be actively maintained by the constant expression of CKIs, whereas the cell cycle–driving cyclins are always present or can be readily elicited. In principle, our findings could find wide application in biotechnology and tissue repair whenever cell proliferation is limiting

Vitamin D in the Prevention, Development and Therapy of Oncological Diseases.

Vitamin D, traditionally known as a fat-soluble essential vitamin, is a precursor of a powerful steroid hormone that regulates a broad spectrum of physiological processes. In addition to its fundamental role in bone metabolism, epidemiological, preclinical and cellular researches in recent decades have revealed that vitamin D can play a considerable role in the prevention of some pathologies, including extra-skeletal ones, such as neoplasms. Vitamin D, as a prohormone, undergoes first hepatic and subsequently renal metabolism to produce a biologically active metabolite, calcitriol or 1α,25-dihydroxyvitamin D or (1,25 (OH)2D), which binds the vitamin D receptor by regulating the expression of several genes involved in bone metabolism and other biological functions. Furthermore, recent studies have revealed that vitamin D can be also metabolized and activated through a non-canonical metabolic pathway catalyzed by CYP11A1, the gene encoding the cholesterol side chain cleavage enzyme or P450scc. The metabolites of vitamin D deriving from the CYP11A1 enzyme have shown antiproliferative and anti-inflammatory activities and are able to promote the differentiation process on neoplastic cells in comparable way or better than calcitriol, thus contributing to its tumor preventive effect. Clinical data have demonstrated that vitamin D has anticancer activity against prostate, colon, and breast cancers. Several molecular mechanisms of vitamin D involved in tumor etiopathogenesis have been proposed that have not yet been fully clarified. Vitamin D may play a key role in preventing the early stage of the neoplastic process by exerting anti-inflammatory, antioxidant defenses and inducing enzymes responsible for repairing DNA damage and could also be involved in mechanisms of inhibition of cell proliferation, induction of cell differentiation, and cell death. In addition, some studies indicate various mechanisms through which vitamin D can quantitatively and qualitatively influence the intestinal microbiota, strongly linked to chronic inflammatory bowel diseases and the development of colon cancer. However, the metabolism and functions of vitamin D are dysregulated in some neoplasms which therefore develop resistance to the antiproliferative effect of vitamin D, and this promotes tumor development and progression. In this review, studies regarding vitamin D in relation to its activity in cancer have been summarized, as long as the metabolic pathways described for vitamin D

Biomimetic Chemistry on Tandem Protein/Lipid Damages under Reductive Radical Stress

The study of radical stress in the biological environment needs a comprehensive vision of all possible reactive species and their mechanisms. Among them, reductive stress is evaluated for its selective target of sulfur-containing compounds. The selective attack of reducing species like H• atoms or eaq?/H+ to sulfur-containing amino acid residues has been proved in different substrates, peptides and proteins. The transformations include methionine to ?-aminobutyric acid and cysteine/cystine residues to alanine, as recognized in several sequences so far, such as RNase A, lysozyme, Met-enkephalin, amyloid ?-peptide and metallothioneins. The amino acid desulfurization is accompanied by the formation of low-molecular-weight sulfur-centered radicals that may cause geometrical cis–trans isomerization of unsaturated fatty acid residues in lipid bilayer. Thus, tandem protein/lipid damage is accomplished. Progress in research has given us a more comprehensive overview of the protein modifications and their roles, and the chemical biology approach will make its vital contribution to the study of free radical reactions, linking chemistry to biology and medicine

Development and Optimization of a Fluorescent Differential Display PCR System for Analyzing the Stress Response in Lactobacillus sakei Strains

Lactobacillus sakei is widely used as starter in the production process of Italian fermented sausages and its growth and survival are affected by various factors. We studied the differential expression of genome in response to different stresses by the fluorescent differential display (FDD) technique. This study resulted in the development and optimization of an innovative technique, with a high level of reproducibility and quality, which allows the identification of gene expression changes associated with different microbial behaviours under different growth conditions

A genomic, transcriptomic and proteomic look at the GE2270 producer Planobispora rosea, an uncommon actinomycete

We report the genome sequence of Planobispora rosea ATCC 53733, a mycelium-forming soil-dweller belonging to one of the lesser studied genera of Actinobacteria and producing the thiopeptide GE2270. The P. rosea genome presents considerable convergence in gene organization and function with other members in the family Streptosporangiaceae, with a significant number (44%) of shared orthologs. Patterns of gene expression in P. rosea cultures during exponential and stationary phase have been analyzed using whole transcriptome shotgun sequencing and by proteome analysis. Among the differentially abundant proteins, those involved in protein metabolism are particularly represented, including the GE2270-insensitive EF-Tu. Two proteins from the pbt cluster, directing GE2270 biosynthesis, slightly increase their abundance values over time. While GE2270 production starts during the exponential phase, most pbt genes, as analyzed by qRT-PCR, are down-regulated. The exception is represented by pbtA, encoding the precursor peptide of the ribosomally synthesized GE2270, whose expression reached the highest level at the entry into stationary phase. Copyright

Bioresorbable reinforcement induces histological rearrangement of pulmonary autograft in an experimental model of Ross operation

The Ross procedure has emerged as a popular choice for aortic valve replacement in infants and children. However, pulmonary artery (PA) autograft dilation remains the major concern; hence, several modifications of the valve implantation techniques, such as reinforcing the autografts with a tubular synthetic mesh, have been reported. With the aim to prevent dilation and permit the normal growth of the neo-aortic root following pulmonary autograft implantation, we assessed the biological effect and long term performance of an external bioresorbable reinforcement for PA autograft in an experimental Ross model in growing animals. An experimental model of translocation of the pulmonary trunk as autograft in aortic position, funded on the Hook’s law and Laplace equilibrium, has been developed and performed under cardiopulmonary bypass in young lambs. The PA without reinforcement (n=5) was compared to PA reinforced with new scaffold polymer with an external armour of Polytetrafluoroethylene. The PA autograft diameter was measured using transoesophageal echography at day 0 and at 6 months and compared to the distal aortic diameter. Pathological analysis of the PA autograft reinforced was performed at 6 months and the results were compared to those of a control group with no reinforcement (n=5) Animal weight was 25+5 kg at day 0 and 58+10 kg at 6 months and the reference aortic diameter increased from 14+1mm at day 0 to 17+2mm at 6 months. With no reinforcement, an instantaneous PA graft distension (27,4+2mm) was noted followed by an aneurysmal formation at 6 months (38+3mm). Reinforcement with scaffold polymer on polidioxanone allowed maintaining the PA graft diameter close to the reference value (17+2mm at day 0). Immunohistochemistry revealed MMP-9 overexpression indicating the induction of a matrix remodeling process that are not detectable in the control group. Mallory staining revealed elastin deposition in the reinforced PA in comparison to the collagen present in the non-reinforced group, reliably suggesting a shift towards an elastic remodeling and arterialization. PicroSirius red staining reveled in the control group collagen fibers non- homogeneously distributed with a increased cellularity indicating inflammatory infiltrates. The reinforced PA displays more organized and dense collagen fibers in the “elastic zone” of the vessel and less pronounced cellular infiltrate. In conclusion, bioresorbable external polydioxanone-based reinforcement allowed a structural rearrangement of PA autograft consisting of media reorganization with an increase in the elastic wall component. Such histological outcome arguably prevented autograft dilation and conferred enhanced mechanical properties on the PA wal